CN107135015A - Electric line carrier wave transmission device and communication system - Google Patents
Electric line carrier wave transmission device and communication system Download PDFInfo
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- CN107135015A CN107135015A CN201710179444.XA CN201710179444A CN107135015A CN 107135015 A CN107135015 A CN 107135015A CN 201710179444 A CN201710179444 A CN 201710179444A CN 107135015 A CN107135015 A CN 107135015A
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- line carrier
- carrier wave
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/26—Systems using multi-frequency codes
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B3/00—Line transmission systems
- H04B3/54—Systems for transmission via power distribution lines
- H04B3/542—Systems for transmission via power distribution lines the information being in digital form
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B3/00—Line transmission systems
- H04B3/54—Systems for transmission via power distribution lines
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
- H04L1/0056—Systems characterized by the type of code used
- H04L1/0071—Use of interleaving
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/08—Arrangements for detecting or preventing errors in the information received by repeating transmission, e.g. Verdan system
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/26—Systems using multi-frequency codes
- H04L27/2601—Multicarrier modulation systems
- H04L27/2602—Signal structure
- H04L27/2605—Symbol extensions, e.g. Zero Tail, Unique Word [UW]
Abstract
The present invention relates to electric line carrier wave transmission device and communication system.Electric line carrier wave transmission device according to an aspect of the present invention is the electric line carrier wave transmission device that transmission symbol is transmitted via transmission path.The transmitting device includes：Frequency/time-interleaved unit, the OFDM modulating units that symbol carries out OFDM modulation that transmit to intertexture being interleaved to transmission symbol；The time domain for repeatedly transmitting the transmission symbol M time (M is the integer more than 1) modulated by the OFDM modulating units in the time domain repeats transmission unit.
Description
The application is divisional application, and the national applications number of original bill is 201310163972.8, and the applying date is May 7 in 2013
Day, entitled " electric line carrier wave transmission device and communication system ".The cross reference of related application
The Japanese patent application No.2012- including specification, accompanying drawing and summary that on May 7th, 2012 submits
105866 entire disclosure is incorporated herein by reference.
Technical field
The present invention relates to device for power line carrier communications and communication system, and relate more specifically to transmit via power line
The device for power line carrier communications and communication system of symbol.
Background technology
Japanese Unexamined Patent Application Publication No.2008-172849 discloses a kind of power-line carrier communication system.Power line
Communication environment it is different according to place and time, and some communication environments may be in terms of its noise conditions or impedance conditions
It is excessively poor.Under such circumstances, using the communication standard (such as G3-PLC and PRIME) of existing OFDM (OFDM)
It is not enough to perform good communication.Therefore, more sane communication means is needed for such environment.
A kind of sane communication means is disclosed in Japanese Unexamined Patent Application Publication No.2008-172849.According to Japan
Redundancy on Unexamined Patent Application Publication No.2008-172849, the robustness passage time axle of the communication means and protected
Hold.For example, when to transmit 80 symbols, being interleaved by 16 kinds of carrier frequencies (public with reference to above patent application to transmit
Fig. 2 and Fig. 3 in opening).Specifically, multiple symbol sequences are created by being resequenced on a timeline to transmission symbol
Row.Then, multiple incoming symbol sequences are modulated (with reference to the 0019 of above patent application publication by different carrier frequencies respectively
Section).Therefore, time-domain-repetitive signal is created in the previous stage (prestage) of frequency interlacing.
The content of the invention
Therefore, become necessary to perform interleaving treatment to each time-domain-repetitive signal.As a result, occurring in that needs mass data
The problem of processing.
The other problems of prior art and the new feature of the present invention are by according to the specification with the present invention and subsequent
The related description of accompanying drawing and disclosed.
According to aspects of the present invention, in electric line carrier wave transmission device, the symbol of intertexture is carried out using OFDM schemes
Modulation, and repeatedly transmit a time domain OFDM signal.
According to this aspect of the invention, it can be handled with low volume data and perform sane communication.
Brief description of the drawings
Fig. 1 is the block diagram for the configuration for showing the power-line carrier communication system according to first embodiment；
Fig. 2 is the detailed configuration for showing the two simulation receiving circuit being arranged in reception device and OFDM demodulation unit
Block diagram；
Fig. 3 is the block diagram for the detailed configuration for showing the time domain synthesis unit in reception device；
Fig. 4 is the timing diagram for schematically showing the symbol used during synthesis in the time domain；
Fig. 5 is the block diagram for showing the communication system according to comparative example；
Fig. 6 is the block diagram for the configuration for showing the power-line carrier communication system according to second embodiment；
Fig. 7 is the block diagram for the configuration for showing the power-line carrier communication system according to 3rd embodiment；
Fig. 8 is the block diagram for the configuration for showing the power-line carrier communication system according to fourth embodiment；And
Fig. 9 is the view for showing the reception symbol sequential according to the power-line carrier communication system of fourth embodiment.
Embodiment
First embodiment
(configured in one piece of system)
Herein with reference to Fig. 1 to the power-line carrier communication system (hereinafter referred to as communication system) according to the embodiment
Configuration be described.Communication system 100 includes transmitting device 1, transmission path 20 and reception device 2.Transmission path 20 is for example
It is the power line for the alternating current (AC electricity) for transmitting 50Hz or 60Hz.Transmitting device 1 and reception device 2 are mutual via transmission path 20
Connection.Transmitting device 1 exports modulation symbol to transmission path 20.Reception device 2 is received by transmitting device 1 via transmission path 20
The symbol exported.By this way, transmitting device 1 and reception device 2 perform data communication each other via transmission path 20.
In this case, communication system 100 performs communication using OFDM schemes.
(transmitting device 1)
Transmitting device 1 includes coding unit 1, S/P converting units 12, frequency/time-interleaved unit 13, OFDM modulating units
14th, time domain repeats transmission unit 15 and analogue transmission circuit 16.
Coding unit 11 performs the coded treatment for being encoded to transmission symbol.Here, it will be assumed that transmission symbol
Data volume is N (N is natural number).For example, coding unit 11 adds the check bit for error correction to transmission symbol.Therefore, pass
The data volume of defeated symbol is multiplied by R, and the data volume of the transmission symbol exported from coding unit 11 is changed into R × N.S/P conversions are single
Member 12 converts serial data into parallel data.By the conversion, transmission symbol is converted into parallel data.Then, S/P is changed
Unit 12 exports the transmission symbol for having been changed to parallel data to frequency/time-interleaved unit 13.
Frequency/time-interleaved unit 13 is interleaved in both frequency domain and time domain to the transmission symbol.In other words, frequency
Rate/time-interleaved unit 13 is performed for the frequency interlacing of Distributed Transmission symbol data in a frequency domain and for dividing in the time domain
Cloth transmits the time-interleaved of symbol data.In frequency interlacing, transmission symbol data is assigned to what the OFDM then described was modulated
Subcarrier.The data volume handled from frequency/time-interleaved unit 13 is changed into R × N.
OFDM modulating units 14 are modulated using OFDM schemes to interleaved transmission symbol data.Because OFDM is adjusted
System is using multiple subcarriers (multiple carrier waves), so transmission symbol data is multiplexed and transmitted parallel.For example, OFDM modulating units
14 are mapped in transmission symbol data on the signaling point in IQ planes.Then, Fourier is performed to the transmission symbol data of mapping
Inverse transformation.When OFDM modulating units 14 are converted to the subcarrier data of intertexture by performing IFFT (Fast Fourier Transform Inverse)
Data on countershaft.By this way, OFDM modulating units 14 create the modulation by the way that transmission symbol is modulated and obtained
Signal.In addition, OFDM modulating units 14 add targeting signal to the front end of modulated signal.The targeting signal be, for example, by using
OFDM schemes are modulated obtained signal to tentation data.Alternatively, the targeting signal can be different from ofdm signal
Signal (such as linear FM signal；chirp signal).Except this is leading, the data quantitative change handled by OFDM modulating units
For R × N.
Time domain repeats transmission unit 15 and repeatedly transmitted in OFDM modulating units 14 by using OFDM modulation to transmission symbol
Number it is modulated an obtained modulated signal.Include being used to store and a symbol for example, time domain repeats transmission unit 15
Buffer of corresponding modulated signal etc..Time domain is repeated transmission unit 15 and repeatedly transmitted with specific Fixed Time Interval by installing
The modulated signal that buffer in time domain repeats transmission unit 15 is stored.Here, it will be assumed that relative with a transmission symbol
The modulated signal answered is repeatedly transmitted M times (M is the number of two or more).In addition, M can be equal to the integer of two or more.At this
In the case of kind, protection interval can not be inserted between the symbol repeatedly transmitted.
The data volume that time domain repeats handled by transmission unit 15 is changed into R × M × N.Transmission unit 15 is repeated by time domain to repeat
The modulated signal of transmission is amplified by the amplifier in analogue transmission circuit 16, and is output to transmission path 20.Such as with
Described by upper, time domain repeats transmission unit 15 and transmits symbol to the repetition M identical of output of transmission path 20.
(reception device 2)
Next, reception device 2 will be described.Reception device 2 includes simulation receiving circuit 21, time domain synthesis unit
22nd, OFDM demodulation unit 23, frequency/time de-interweaving unit 24, P/S converting units 25 and decoding unit 26.
Simulation receiving unit 21 receives the modulated signal transmitted by transmitting device 1 via transmission path 20.In this feelings
Under condition, due to providing alternating current to transmission path 20, so the voltage of alternating current is superimposed in modulated signal.Simulation receives electricity
Road 21 includes amplifier, and the amplifier is amplified using predefined gain to received reception signal.The reception is believed
Number include repeating the M symbol that the transmission transmission symbol of M times is created by transmitting device 1 (wherein M is the number of symbol).This
Outside, the reception signal is included added to the leading of the front end of symbol.Then, the reception signal of 21 pairs of amplifications of simulation receiving circuit enters
Row AD conversion, and to time domain synthesis unit 22 export AD conversion signal.In addition, will be then to simulation receiving circuit 21 institute
The processing of execution is described in detail.
Time domain synthesis unit 22 is repeatedly transmitted M symbol being created for M times using transmission symbol to perform in the time domain
Synthesis.It is averaged for example, 22 pairs of time domain synthesis unit transmission symbols are repeatedly transmitted the M symbol created for M times.In other words
Say, time domain synthesis unit 22 is repeatedly transmitted the M symbol created for M time using transmission symbol and receives symbol to synthesize one.
In addition, then the processing performed by time domain synthesis unit 22 will be described in detail.Transmission symbol is repeatedly transmitted M times and created
The M symbol built is converted into a reception symbol.Therefore, after that transition, data volume is changed into M/mono-, and will be by
OFDM demodulation unit 23 is changed into R × N in the data volume that rear stage is handled.
OFDM demodulation unit 23 is solved using OFDM schemes come the reception signal to reception symbol synthesized in time domain
Adjust.In addition, then the processing performed by OFDM demodulation unit 23 will be described in detail.Frequency/time de-interweaving unit 24
Reception symbol included in the reception signal that is demodulated using OFDM schemes is deinterleaved.Frequency/time de-interweaving unit
24 perform deinterleaving with the opposite order of the intertexture of frequency/execution of time-interleaved unit 13., will be in frequency domain using the deinterleaving
Its home position is returned with the data of distribution in both time domains.Data volume handled by frequency/time de-interweaving unit 24
It is changed into R × N.
P/S converting units 25 change the parallel data of the reception symbol deinterleaved by frequency/time de-interweaving unit 24
For serial data.P/S converting units 25 export the reception symbol for being converted to serial data to decoding unit 26.Then, decode single
The data for the reception symbol that 26 pairs of member is converted to serial data are decoded.Volume of the decoding unit 26 to be performed with coding unit 11
The anti-order of code-phase is decoded to the data for receiving symbol.Using the decoding, receive the data volume of symbol from R × N become again for
N。
Next, by reference Fig. 2 to performed by the processing performed by simulation receiving circuit and OFDM demodulation unit 23
Processing is described in detail.Fig. 2 is the block diagram for showing to simulate the configuration example of receiving circuit 21 and OFDM modulating units 23.
(simulation receiving circuit 21)
First, the configuration for simulating receiving circuit 21 will be described.Simulating receiving circuit 21 includes coupler 44, receives
Amplifier 41, ADC (analog-digital converter) 42 and acquisition AGC (automatic growth control) synchronization unit 43.
Coupler 44 is coupled with transmission path 20, and receives the reception signal propagated by transmission path 20.
Next, coupler 44 is by the reception signal output to receiving filter 45.Coupler 44 and receiving filter 45 believe OFDM
Number with exchange electrically separated.Reception amplifier 41 is received via coupler 44 and receiving filter 45 and passed by transmission path 20
The reception signal broadcast, and the reception signal is amplified using predefined gain.ADC42 passes through to reception amplifier
The 41 reception signals amplified are AD converted to create digital received signals.Obtain AGC synchronization units 43 and adjust to receive and amplify
The gain of device 41.For example, when detecting predetermined preambles, AGC synchronization units 43 are obtained based on being obtained after AD conversion
Digital received signals, reception gain is adjusted according to the incoming level to ADC 42.In other words, detect with it is leading relative
During the targeting signal answered, obtain gain of the AGC synchronization units 43 to reception amplifier 41 and be adjusted.
In addition, obtain AGC synchronization units 43 sets up frame synchronization by detecting the border between targeting signal and payload.Obtain
AGC synchronization units 43 are taken to notify this to be used for frame synchronization to the FFT unit 27 of time domain synthesis unit 22 and OFDM demodulation unit 23
Regularly.Notified due to more than, time domain synthesis unit 22 and OFDM demodulation unit 23 can be operated synchronously with one another.For example,
When detecting leading in the reception signal obtained after AD conversion, before obtaining AGC synchronization units 43 according to detecting
The timing led is adjusted as the timing of the processing performed by time domain synthesis unit 22.Utilize the regulation, the Signed Edge of replicator
Boundary is determined.Then, time domain synthesis unit 22 uses the biography with predefined symbol lengths by being repeatedly transmitted M times
M symbol that defeated symbol is created performs time history synthesis.In the similar mode with more than, obtain AGC synchronization units 43 according to
The processing performed by FFT unit is controlled according to detected leading timing.
(OFDM demodulation unit 23)
OFDM demodulation unit 23 includes the FFT unit 27 to receiving symbol progress Fourier transformation and performs demapping
De-mapping unit 28.For example, 27 pairs of data as the reception symbol synthesized by time domain synthesis unit 22 of FFT unit perform FFT (soon
Fast Fourier transformation) so that the data of the reception symbol to be transformed to the complex data in frequency domain.Next, the domain complex data
It is demodulated by the point described in the complex number plane of the demapping of de-mapping unit 28 by the domain complex data, its
Result is the data for retrieving the reception symbol.In addition, the timing of the processing performed by FFT unit 27 is synchronous by obtaining AGC
Unit 43 is controlled.Using above control, symbol can be received to one synthesized by time domain synthesis unit 22 with properly timed
Perform FFT.Then, the data of the reception symbol obtained after demapping are output to frequency/time de-interweaving unit 24.
(time domain synthesis unit 22)
Next, the processing performed by time domain synthesis unit 22 will be described with reference to Fig. 3 and Fig. 4.Fig. 3 is when showing
The block diagram of the example of the configuration of domain synthesis unit 22.Fig. 4 is to be shown with symbol to perform synthesis in the time domain and create reception
The timing diagram of the processing of symbol.Fig. 4 shows the example that a transmission symbol is repeatedly transmitted four times.
Time domain synthesis unit 22 includes symbol waveform synthesis unit 31 and noise detection unit 32.Symbol waveform synthesis unit
31 pairs of transmission symbols are repeatedly transmitted the M symbol created for M times and are averaged.For example, as shown in Figure 4, it will be assumed that by passing
Defeated symbol, which is repeatedly transmitted first group of four symbol created for four times, includes symbol S1-1, S1-2, S1-3 and S1-4.With similar
Mode, it will be assumed that by transmit symbol be repeatedly transmitted second group of four symbol created for four times include symbol S2-1,
S2-2, S2-3 and S2-4.For example, symbol S1-1, S1-2, S1-3 and S1-4 and symbol S2-1, S2-2, S2-3 and S2-4 have
Identical symbol lengths, and they are continuously transferred.
Symbol waveform synthesis unit 31 exports the symbol waveform of synthesis to OFDM demodulation unit 23.Although can have various
Synthetic method, but it will be assumed to carry out symbol S1-1 to S1-4 using wherein symbol waveform synthesis unit 31 in this case
Average method.The leading front end for being added into the first symbol S1-1.As described above, symbol waveform synthesis unit 31
To be averaged to symbol S1-1 to S1-4 according to timing of the AGC synchronization units 43 to detection of preamble is obtained.Stated differently, since obtaining
AGC synchronization units 43 are taken to have been detected by leading, so symbol waveform synthesis unit 31 is able to detect that in symbol S1-1 to S1-
Border between 4.Due to the detection, symbol waveform synthesis unit 31 can be averaged to symbol S1-1 to S1-4 and be connect with synthesizing
Receive symbol R1.By this way, symbol waveform synthesis unit 31 at this by (showing being repeatedly transmitted M times by transmitting symbol
In example, M=4) four symbol S1-1 to S1-4 being created carry out average receiving symbol R1 to synthesize one.
Here, although symbol S1-1 to S1-4 has identical signal waveform in the side of transmitting device 1, but is due to including passing
The communication environment of the defeated grade of path 20 and cause these symbols that there are different signal waveforms in the side of reception device 2.If for example,
Noise is generated in transmission path 20, then simulates receiving circuit 21 and receives with the reception letter that noisy symbol is superimposed thereon
Number.
In the case where noise is superimposed on symbol, worry by being demodulated obtained reception symbol to symbol
Data are simultaneously incorrect.Therefore, in this embodiment, the noise generated in the detection of noise detection unit 32 transmission path 20.Noise
Detection unit 32 is to the output noise testing result of symbol waveform synthesis unit 31.Then, symbol waveform synthesis unit 31 is used and removed
Symbol outside the symbol that the timing of noise measuring is obtained performs synthesis.
For example, as shown in Figure 4, it will be assumed that generate noise in symbol S2-2s of the symbol S2-1 into S2-4.This
In the case of, symbol S2-1, symbol S2-3 and symbol S2-4 of 31 pairs of the symbol waveform synthesis unit in addition to symbol S2-2 are carried out
It is average.In other words, symbol waveform synthesis unit 31 averagely receives symbol R2 by being carried out to three above symbol to calculate.It is logical
Often, symbol waveform synthesis unit 31 by transmitting symbol in the time domain to except being repeatedly transmitted M (M=in this case
4) symbol outside some symbols in the M symbol created is averaged.Then, as described above, by average
The reception symbol calculated carries out OFDM demodulation by OFDM demodulation unit 23.
For example, noise detection unit 32 calculates the power of each symbol.If being mixed with noise in symbol, the symbol
Power become much larger.Therefore, if noise detection unit 32 receives the symbol that its power is equal to or more than specific threshold,
Noise detection unit 32 judges to be mixed with noise in the symbol.Noise detection unit 32 notifies to make an uproar to symbol waveform synthesis unit 31
Sound detection result.31 pairs of symbols in addition to mixing noisy symbol S2-2 of symbol waveform synthesis unit are averaged.Cause
For threshold value of the power more than M symbol of symbol S2-2 reception signal, so the M symbol of use of symbol waveform synthesis unit 31
The central symbol in addition to symbol S2-2 performs synthesis.In this way, the noise generated suddenly can be reduced not
Profit influence.
Alternatively, additionally it is possible to no matter it is contemplated that existing or in the absence of noise, without installation noise detection unit
32 time domain synthesis unit 22, which is all used, to be repeatedly transmitted the M symbol created for M times by transmitting symbol and performs synthesis.Change
Sentence is talked about, can be to by transmitting all M that symbol is repeatedly transmitted M times and created no matter existing or in the absence of noise
Individual symbol is averaged.Additionally it is possible to which it is contemplated that time domain synthesis unit 22 uses M by Maximal ratio combiner method etc.
Individual symbol performs synthesis.
In addition, being interleaved in transmission symbol with after OFDM modulation, time domain repeats transmission unit 15 and repeatedly transmits transmission symbol
Number M times.Using above procedure, it can reduce as the processing handled by frequency/time-interleaved unit 13 and OFDM modulating units 14
Amount.Stated differently, since can reduce by the data processing amount handled by FFT and intertexture, so data processing can be reduced
Total amount.Therefore, it is possible to shorten processing time.
For example, as shown by Fig. 5 by comparative example, it will be assumed that sequentially the transmission with data volume N is accorded with this
Number perform coding, S/P conversions, time domain and repeat transmission, frequency interlacing and OFDM modulation.If data volume is multiplied by R in coding, and
And transmission symbol be repeatedly transmitted M time in the time domain, then by frequency interlacing and OFDM modulation handled by data volume be changed into R ×
M×N.Therefore, it is changed into Fig. 1 residing from frequency/time-interleaved unit 13 and from the data volume handled by OFDM modulating units 14
M times of the data volume of reason.In a similar way, in reception device 2, handed over by OFDM demodulation unit 23 and by frequency/time solution
Knit M times that the data volume handled by unit 24 is changed into data volume handled in Fig. 1.This means OFDM modulation and demodulation processing
And intertexture conciliates the quantitative change of interleaving treatment to modulate M times of handled data volume in Fig. 1 by OFDM.
On the other hand, in the implementation shown in fig. 1, it is possible to reduce by OFDM demodulation unit 23 and frequency/time de-interweaving
Data volume handled by unit 24.In addition, time domain repetition transmission unit 15 merely has to repeatedly transmit and is stored in buffer etc.
Same-sign.Therefore, repeating the calculating of transmission just becomes to be not necessarily to, and this causes the simplification of repetition transmission process.In addition, in figure
In 1, reception device 2 performs OFDM demodulation and deinterleaving after being synthesized by time domain synthesis unit 22.Therefore, in Fig. 1,
It can also reduce in reception device 2 as the data volume handled by OFDM demodulation unit 23 and frequency/time de-interweaving unit 24.Such as
Described above, the robust communications using low volume data can be realized according to this embodiment of the invention.
In this embodiment it is possible to not insert protection interval between symbol as shown in Figure 4.In other words, first group
First symbol S2-1 in last symbol S1-4 and the second group code in symbol is continuously transferred.Symbol S1-1 to S1-4
Created based on identical traffic symbol.Therefore, in the absence of noise, symbol S1-1 to S1-4 is received as almost identical
Signal.In a similar way, symbol S2-1 to S2-4 is received as almost identical signal under the same conditions.
In addition, the part that created symbol is repeatedly transmitted by transmitting symbol may be used as protection interval.Specifically
Ground says, by transmitting, symbol is repeatedly transmitted the beginning of the M symbol created for M times or latter end may be used as protection
Interval.By using the beginning or latter end of M symbol as protection interval, it can suppress to cause due to multipath
Demodulation characteristics variation.Further, since there is no protection interval between M symbol, can be by effective profit so receiving signal
With which results in the improvement of the reception characteristic of the reception device according to the embodiment.In addition, with to each symbol addition protection between
Every general OFDM modulation schemes compare, transmission rate can more effectively be prevented according to the OFDM modulation schemes of the embodiment
Variation.
On the other hand, in the configuration of the comparative example shown in Fig. 5, symbol by repeatedly transmitting transmission symbol in the time domain
It is interleaved after number being created.Therefore, the symbol continuously transmitted is different from each other.Result, it is necessary to be modulated by general OFDM
Protection interval is inserted between the symbol that scheme is transmitted.Due to inserting protection interval between symbols, so the comparative example
Transmission rate be less than the embodiment transmission rate.
Second embodiment
Communication system 102 according to the embodiment is described reference Fig. 6.In this embodiment, OFDM demodulation
The OFDM demodulation unit 23 and time domain synthesis unit 22 of the deployment order and first embodiment of unit 23 and time domain synthesis unit 22
Deployment order it is opposite.The deployment of other units in addition to OFDM demodulation unit 23 and time domain synthesis unit 22 is real with first
The identical of example is applied, the explanation related to other units in the embodiment will be omitted.
In a second embodiment, after OFDM demodulation unit 23 carries out OFDM demodulation to symbol, time domain synthesis unit 22
Synthesized using these semiology analysis.In other words, after by OFDM demodulation unit 23 to semiology analysis FFT and demapping, when
Domain synthesis unit 22 performs synthesis using these symbols.Then, the reception symbol synthesized by time domain synthesis unit 22 by frequency/
Time de-interweaving unit 24 is deinterleaved.Therefore, R × N is changed into from the data volume handled by frequency/time de-interweaving unit.
Using configuration described above, it can also reduce as the data volume handled by frequency/time de-interweaving unit 24.
In addition, the configuration shown in Fig. 6 is effective in the case of FFT size very little of the number of sub carrier wave relative to FFT.For example,
There are following situations, entered in a frequency domain by FFT after line translation in this case, symbol is in the part without using frequency band
In the case of mapped.For example, there are the feelings that 100 subcarriers being used only in 500 subcarriers are mapped symbol
Condition.In this case, data volume can effectively be reduced.According to the embodiment, it can realize using the sane of low volume data
Communication.
Here, time domain synthesis unit 22 calculates the average value of the coordinate in IQ planes.Specifically, ofdm demodulator unit 23
Calculate coordinates of the symbol S1-1 to S1-4 in IQ planes.Then, time domain synthesis unit 22 uses symbol S1-1 to S1-4 seat
Target average value receives position of the symbol in IQ planes to calculate.Calculated, easily can closed in the time domain by such
Into reception symbol.
In addition, such as the situation in first embodiment, alternatively it is conceivable to, based on noise measuring result come according to very useful in average
Symbol.In other words, alternatively it is conceivable to, the symbol transmitted when existing and largely making an uproar is not used to average.Self-evidently,
No matter existing or symbol can be averaged in the absence of noise.
3rd embodiment
Conciliate according to the FFT unit 27 that the OFDM demodulation unit 23 of first embodiment includes deployment order as shown in Figure 2
Map unit 28.In this embodiment, FFT unit 27, time domain synthesis unit 22 and the carry out portion as shown in Figure 7 of de-mapping unit 28
Administration.In other words, after FFT unit 23 performs FFT processing, time domain synthesis unit 22 performs synthesis in the time domain.In addition,
Performed in the time domain by time domain synthesis unit 22 after synthesizing, de-mapping unit 28 performs demapping.
Time domain synthesis unit 22 average synthesizes reception symbol by being carried out to the data of symbol in units of frequency.Example
Such as, FFT unit 27 performs FFT to each of symbol S1-1 into S1-4.22 pairs of time domain synthesis unit is performed to it
FFT symbol S1-1 to S1-4 frequency domain data is averaged.The frequency domain data for receiving symbol is averagely calculated more than.With
Afterwards, de-mapping unit 28 based on average frequency data come to receive semiology analysis demapping.
Even with such configuration, also frequency/time de-interweaving unit 24 can be reduced such as the situation of second embodiment
Handled data volume.Further, it is also possible to which so that the data volume handled by de-mapping unit 28 is R × N.In addition, shown in Fig. 7
It is effective to configure in the case of FFT size very little of the number on FFT of subcarrier.For example, there are following situations, at this
In situation, entered in a frequency domain by FFT after line translation, symbol is reflected in the case of the part without using frequency band
Penetrate.For example, there is a situation where that 100 subcarriers being used only in 500 subcarriers are mapped symbol.In such feelings
Under condition, data volume can be effectively reduced.Therefore, it is possible to realize the robust communications using low volume data according to the embodiment.This
Outside, in the 3rd embodiment, as the situation in first embodiment, alternatively it is conceivable to determine to be used to put down based on noise measuring result
Equal symbol.In other words, alternatively it is conceivable to which the symbol transmitted when there is much noise is not used in average.It is self-evident
It is, no matter existing or symbol can be averaged in the absence of noise.
Fourth embodiment
The communication system 104 according to the embodiment will be described with reference to Fig. 8.Fig. 8 is shown according to the embodiment
The block diagram of the configuration of communication system.In addition to the configuration of second embodiment, include zero according to the communication system 104 of the embodiment
Cross detection unit 51, zero cross detection unit 52 and transmission path property (profile) measuring unit 53.Here, due to except
Other units beyond zero cross detection unit 51, zero cross detection unit 52 and transmission path property measuring unit 53 are matched somebody with somebody
Put identical with those included in first embodiment or second embodiment, so the explanation about those units will be omitted.
Transmitting device 1d includes zero cross detection unit 51.Zero cross detection unit 51 is based on transmitting by transmission path 20
The zero cross point of alternating current detect the phase of alternating current.Then, zero cross detection unit 51 is defeated by detected phase
Go out to time domain and repeat transmission unit 15.
Time domain repeats transmission unit 15 based on the phase detected by zero cross detection unit 51 come to repeatedly transmitting transmission
The timing of signal is controlled.For example, time domain repeats transmission unit 15 is set to exchange by the repetition transmission cycle for transmitting symbol
K times (wherein K is natural number) of the half period of electricity.In other words, the repetition transmission cycle of transmission symbol is in transmission path 20
K/2 times of cycle of alternating current.When the repetition transmission cycle of transmission symbol is required for transmission symbol is repeatedly transmitted M times
Between, but do not include the time required for leading grade.In example described above, repeat transmission cycle and be changed into symbol S1-1
M times of symbol lengths.Alternatively, zero cross detection unit 51 included in transmission unit 1d can be sensed by exchange
Timer of the phase of electric power etc. is substituted.
Here, it will be assumed that a cycle of transmission symbol is the time once transmitted in M transmission for transmit symbol.Change
Sentence is talked about, and a cycle of transmission symbol is to repeat M/mono- of transmission cycle.In example described above, transmission symbol
Number a cycle be changed into symbol S1-1 symbol lengths.If the cycle of alternating current is not the whole of a cycle of transmission symbol
Several times, then last symbol will overflow (run off) alternating electromotive force cycle.In this case, it will be assumed that using last symbol
Number data previous section.In other words so that symbol last in the symbol created for M times will be transmitted by receiving signal
Symbol lengths it is more shorter than other symbols.The symbol lengths of last symbol by shortening, the timing energy of last sign-off
Enough cycles with alternating electromotive force match.Alternatively, the symbol lengths of first symbol can be shortened to substitute last symbol
Number symbol lengths shortening.By this way, time domain repeats cycle of the transmission unit 15 based on alternating current come to transmission symbol
Repetition transmission cycle and transmit symbol a cycle be adjusted.
Reception device 2d includes zero cross detection unit 52 and transmission path property measuring unit 53.Such as zero cross detection list
The situation of member 51, the phase for the alternating current that the detection of zero cross detection unit 52 is transmitted by transmission path 20.Then, zero crossing is examined
Unit 52 is surveyed by detected phase output to transmission path property measuring unit 53.
Transmission path property measuring unit 53 measures the attribute of transmission path 20.Transmission path property measuring unit 53 is connecing
The attribute for the transmission path 20 that measurement in advance was circulated and changed with the half period of alternating current before receiving frame.Transmission path property is measured
Unit 53 is determined based on measured transmission path property by receiving between the symbol that symbol is repeatedly transmitted and created
Character boundary.Then, time domain synthesis unit 22 and OFDM demodulation unit 23 are based on by the institute of transmission path property measuring unit 53 really
Fixed character boundary performs the processing of their own.In other words, by being accorded with determined by transmission path property measuring unit 53
Number boundary performs OFDM demodulation and synthesis.
One example of property measurements is wherein to use to be practically without transmitting any in the half period of alternating current
The average value of the absolute value of measured reception signal, the method to estimate noisiness change during the time of signal.As when
Domain synthetic method, alternatively it is conceivable to high specific synthetic method, wherein to each estimated by the result that is measured from transmission path property
The SNR (signal to noise ratio) of symbol is used.In the method, become because the symbol corresponding with bad transmission path property has
The SNR of difference, so they have low weight.
Transmission path property measuring unit 53 in reception device allows OFDM demodulation unit 23 to reception
The character boundary of signal is adjusted, in order to match with corresponding transmission path property.Therefore, it is possible to receive be deteriorated compared with
Much less symbol, which results in the improvement for receiving characteristic.For example, the friendship of noise often on power line in transmission path 20
Flow and generated at some phase of electricity.Therefore, it is possible to improve reception characteristic by determining character boundary based on transmission path property.
For example, as shown in Figure 9, it will be assumed that generated at the particular phases of alternating current of the noise in transmission path 20.Making an uproar
When sound is generated, the demodulation characteristics of symbol are deteriorated.In the example depicted in fig. 9, made an uproar with the circulation generation of 180 ° of phases of alternating current
Sound.Fig. 9 shows that noise is generated near the border between symbol S1-4 and symbol S2-1.The cycle bridging of noise generation
(straddle) two symbols S1-4 and S2-1.In a similar manner, near border of the noise between symbol S2-4 and S3-1
Generation.Therefore, the noise is superimposed upon by transmitting four symbol S2-1 to S2-4 that symbol is created for four times by transmission respectively
In two symbol S2-1 to S2-4 on.In other words, by transmitting four symbol S2-1 that symbol is created for four times by transmission
Include and symbol S2-2 and symbol S2-3 that good transmission path attribute is corresponding and relative with bad transmission property to S2-4
The symbol S2-1 and symbol S2-4 answered.Therefore, in four symbols that transmission symbol is created for four times by transmission, only and transmission
Two corresponding symbols of the good properties in path 20.When noise detection unit 32 detects noise, symbol Waveform composition list
Member 31 is averaged without using symbol S2-1 and symbol S2-4.
Therefore, in this embodiment, determine that character boundary is reduced corresponding with the bad attribute of transmission path 20
Number of symbols.Fig. 9 shows the symbol Sa1-1 with the character boundary determined by reception device 2d reception processing to symbol
Sa3-3.Character boundary is determined to be the cycle for making call sign Sa2-1 cover noise generation.In other words, transmission path property is surveyed
Measure unit 53 and determine character boundary so that the cycle of noise generation does not bridge multiple symbols.In this case, although noise
It is superimposed on symbol Sa2-4, but the noise is not superimposed upon symbol Sa2-1 in any one into Sa2-3.Therefore,
By transmitting in four symbols that symbol is created for four times by transmission, exist corresponding with the good properties of transmission path 20
Three symbols.In other words, three symbols corresponding with the good properties of transmission path 20 can be used to perform demodulation, this
Cause the improvement for receiving characteristic.
In the above described manner, when a frame is received, character boundary is determined based on the result of transmission path property measurement.At this
In the case of, abandon the symbol corresponding with the bad attribute of transmission path, and the phase of alternating current is determined so that and well
The corresponding number of symbols of attribute becomes as big as possible.In other words, character boundary is determined so that the symbolic number to be abandoned
Mesh becomes as small as possible.In this case, character boundary is not necessarily to consistent with the character boundary set in transmitting device side.
Reason is, is created because symbol is repeatedly transmitted by identical traffic symbol, and the symbol is identical, and
Using wherein between symbols without using the transmission method of protection interval.Therefore, it is possible to easily improve reception characteristic.In addition,
Symbol S1-1 to S1-4 transmits symbol to create based on identical.Therefore, even if receiving the character boundary of signal independently of transmission
Device 1d sides and be determined in reception device 2d sides, can also prevent receive characteristic variation.
In the fourth embodiment, although property measurement function is added to second embodiment, but the property measurement work(
Also first embodiment or 3rd embodiment can be added into.In addition, in the fourth embodiment, alternatively it is conceivable to, no matter
It can be performed in the presence of or in the absence of noise average.Alternatively, additionally it is possible to it is contemplated that using such as high specific synthetic method
Another synthetic method it is average to substitute.Additionally it is possible to which it is contemplated that appropriately combined first embodiment is into fourth embodiment
Some.
It is of the invention although having been based on the present invention that some embodiments realize inventor to have been described in detail
Embodiments described above is not limited to, and self-evidently, can be in the spirit and model without departing from the present invention
In the case of enclosing, various modifications are carried out to embodiments described above.
Claims (6)
1. a kind of be used to transmit the electric line carrier wave transmission device for transmitting symbol via power line, the power line carrier transmission dress
Put including：
Interleave unit, the interleave unit is used to be interleaved the transmission symbol；
Modulating unit, the transmission symbol that the modulating unit is used to interweave to the interleave unit is modulated；And
Transmission unit, the transmission unit is used to repeatedly transmit transmission symbol M time (the wherein M modulated by the modulating unit
It is greater than 1 integer),
Wherein, by repeatedly transmitting the secondary M symbol generated of the transmission symbol M by the transmission unit, (wherein M represents symbol
Number number) not in-between addition protection interval in the case of transmitted.
2. electric line carrier wave transmission device according to claim 1, wherein, the modulating unit is to interleave unit profit
The transmission symbol interweaved with OFDM (OFDM) scheme is modulated.
3. electric line carrier wave transmission device according to claim 1, wherein, the modulating unit passes through in the list that interweaves
The data of the transmission symbol are concurrently multiplexed in member using the subcarrier of appointment.
4. electric line carrier wave transmission device according to claim 1, further comprises detector, the detector is used to examine
The phase of the alternating current of the power line is surveyed, wherein, cycle of the transmission unit based on the alternating electromotive force on the power line
To adjust the repetition transmission cycle of the transmission symbol and repeat to transmit a cycle of symbol.
5. electric line carrier wave transmission device according to claim 4, wherein, the cycle for repeating transmission is the exchange
K/2 times (wherein K is natural number) in the cycle of electricity.
6. electric line carrier wave transmission device according to claim 1, wherein, the transmission unit repeatedly transmit be stored in it is slow
The identical traffic symbol rushed in device.
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| JP2012105866A JP6017177B2 (en) | 2012-05-07 | 2012-05-07 | Power line carrier transmitter and communication system |
| JP2012-105866 | 2012-05-07 | ||
| CN201310163972.8A CN103391115B (en) | 2012-05-07 | 2013-05-07 | Power line carrier transmission apparatus and communication system |
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| US (2) | US9065543B2 (en) |
| EP (1) | EP2663006B1 (en) |
| JP (1) | JP6017177B2 (en) |
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| JP6017177B2 (en) * | 2012-05-07 | 2016-10-26 | ルネサスエレクトロニクス株式会社 | Power line carrier transmitter and communication system |
| JP2014165898A (en) * | 2013-02-28 | 2014-09-08 | Renesas Electronics Corp | Communication device, communication system, and communication method |
| EP3011732B1 (en) | 2013-06-19 | 2020-04-08 | LG Electronics Inc. | Method and apparatus for transmitting/receiving broadcast signals |
| CN111064549B (en) * | 2013-11-11 | 2022-07-19 | Lg 电子株式会社 | Apparatus and method for transmitting broadcast signal and apparatus and method for receiving broadcast signal |
| FR3019413B1 (en) * | 2014-04-01 | 2017-09-15 | Univ Joseph Fourier | RADIO COMMUNICATION METHOD OF DIGITAL DATA IN A NOISE ENVIRONMENT |
| CN105227214A (en) * | 2014-06-27 | 2016-01-06 | 无锡汉兴电子有限公司 | A kind of power line communication receiving system and method for reseptance |
| JP6405051B2 (en) | 2015-01-05 | 2018-10-17 | エルジー エレクトロニクス インコーポレイティド | Broadcast signal transmitting apparatus, broadcast signal receiving apparatus, broadcast signal transmitting method, and broadcast signal receiving method |
| JPWO2016136491A1 (en) * | 2015-02-23 | 2017-12-28 | 京セラ株式会社 | Transmitting apparatus and receiving apparatus |
| CN107181505A (en) * | 2016-03-10 | 2017-09-19 | 杭州炬华科技股份有限公司 | The data transmission method and device of a kind of power line carrier, PLC |
| JP6713427B2 (en) * | 2017-03-27 | 2020-06-24 | 日立オートモティブシステムズ株式会社 | Load drive system and load drive method |
| FR3093838B1 (en) * | 2019-03-14 | 2022-04-29 | St Microelectronics Sa | Data communication circuit |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6288631B1 (en) * | 1998-12-08 | 2001-09-11 | Matsushita Electric Industrial Co., Ltd. | Power-line carrier communications system |
| US20040160990A1 (en) * | 2002-09-25 | 2004-08-19 | Oleg Logvinov | Method and system for timing controlled signal transmission in a point to multipoint power line communications system |
| US20110110459A1 (en) * | 2004-02-02 | 2011-05-12 | Satius Holding, Inc. | FM OFDM over various communication media |
| US20110143694A1 (en) * | 2005-01-21 | 2011-06-16 | Ryuichi Iwamura | Configurable Frequency Band Elimination For Powerline Network |
| CN102113233A (en) * | 2008-06-06 | 2011-06-29 | 马克西姆综合产品公司 | System and method for applying multi-tone OFDM based communications within a prescribed frequency range |
| US20120099628A1 (en) * | 2010-10-21 | 2012-04-26 | Texas Instruments Incorporated | Symbol-Level Repetition Coding in Power Line Communications |
Family Cites Families (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11266190A (en) * | 1998-03-17 | 1999-09-28 | Sekisui Chem Co Ltd | Electrical lamp communication transmitting and receiving device, and electrical lamp line communication device and method |
| JP2000022771A (en) * | 1998-07-01 | 2000-01-21 | Nec Corp | Reception method in fallback mode and receiver |
| JP4328176B2 (en) * | 2002-10-24 | 2009-09-09 | パナソニック株式会社 | COMMUNICATION DEVICE AND COMMUNICATION METHOD RESISTANT TO BURST ERROR, PROGRAM FOR EXECUTING THE COMMUNICATION METHOD, AND COMPUTER-READABLE RECORDING MEDIUM CONTAINING THE PROGRAM |
| US7418042B2 (en) | 2003-09-17 | 2008-08-26 | Atheros Communications, Inc. | Repetition coding for a wireless system |
| KR100742128B1 (en) * | 2004-10-15 | 2007-07-24 | 삼성전자주식회사 | Apparatus and method for estimating uplink frequency offset in orthogonal frequency division multiplexing communication system |
| CN100481827C (en) * | 2005-12-14 | 2009-04-22 | 北京交通大学 | DFDM system time-frequency domain hybrid difference modulating method |
| JP4649597B2 (en) * | 2006-02-22 | 2011-03-09 | 独立行政法人産業技術総合研究所 | Data transmission device |
| JP4726829B2 (en) * | 2007-03-05 | 2011-07-20 | 三菱電機株式会社 | Electric line carrier communication system |
| JP4474481B2 (en) | 2009-01-06 | 2010-06-02 | 株式会社日立製作所 | Power line carrier system |
| US20110043340A1 (en) | 2009-08-19 | 2011-02-24 | Texas Instruments Incorporated | Concatenated Repetition Code with Convolutional Code |
| JP5160599B2 (en) * | 2010-07-28 | 2013-03-13 | 株式会社近計システム | Power line carrier communication system, power line carrier communication method, program, and recording medium |
| CN102594406A (en) * | 2012-02-17 | 2012-07-18 | 钜泉光电科技(上海)股份有限公司 | Power line carrier communication system and communication method |
| JP6017177B2 (en) * | 2012-05-07 | 2016-10-26 | ルネサスエレクトロニクス株式会社 | Power line carrier transmitter and communication system |
-
2012
- 2012-05-07 JP JP2012105866A patent/JP6017177B2/en active Active
-
2013
- 2013-04-11 US US13/861,320 patent/US9065543B2/en active Active
- 2013-04-17 TW TW102113661A patent/TWI596914B/en active
- 2013-04-17 TW TW106117070A patent/TWI634757B/en active
- 2013-04-25 EP EP13165324.8A patent/EP2663006B1/en active Active
- 2013-05-06 KR KR1020130050529A patent/KR102110239B1/en active IP Right Grant
- 2013-05-07 CN CN201310163972.8A patent/CN103391115B/en active Active
- 2013-05-07 CN CN201710179444.XA patent/CN107135015B/en active Active
-
2015
- 2015-06-19 US US14/744,923 patent/US9344149B2/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6288631B1 (en) * | 1998-12-08 | 2001-09-11 | Matsushita Electric Industrial Co., Ltd. | Power-line carrier communications system |
| US20040160990A1 (en) * | 2002-09-25 | 2004-08-19 | Oleg Logvinov | Method and system for timing controlled signal transmission in a point to multipoint power line communications system |
| US20110110459A1 (en) * | 2004-02-02 | 2011-05-12 | Satius Holding, Inc. | FM OFDM over various communication media |
| US20110143694A1 (en) * | 2005-01-21 | 2011-06-16 | Ryuichi Iwamura | Configurable Frequency Band Elimination For Powerline Network |
| CN102113233A (en) * | 2008-06-06 | 2011-06-29 | 马克西姆综合产品公司 | System and method for applying multi-tone OFDM based communications within a prescribed frequency range |
| US20120099628A1 (en) * | 2010-10-21 | 2012-04-26 | Texas Instruments Incorporated | Symbol-Level Repetition Coding in Power Line Communications |
Also Published As
| Publication number | Publication date |
|---|---|
| EP2663006B1 (en) | 2020-08-05 |
| EP2663006A3 (en) | 2018-01-31 |
| KR102110239B1 (en) | 2020-05-13 |
| EP2663006A2 (en) | 2013-11-13 |
| JP6017177B2 (en) | 2016-10-26 |
| TW201729549A (en) | 2017-08-16 |
| TW201404059A (en) | 2014-01-16 |
| TWI596914B (en) | 2017-08-21 |
| CN103391115B (en) | 2017-04-26 |
| CN107135015B (en) | 2021-06-04 |
| US20150288420A1 (en) | 2015-10-08 |
| US9065543B2 (en) | 2015-06-23 |
| CN103391115A (en) | 2013-11-13 |
| KR20130124903A (en) | 2013-11-15 |
| JP2013236155A (en) | 2013-11-21 |
| US20130294532A1 (en) | 2013-11-07 |
| US9344149B2 (en) | 2016-05-17 |
| TWI634757B (en) | 2018-09-01 |
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